In recent years, the applications of audio and video signals have been constantly widened and improved. For example, video compact disk (VCD), digital versatile disk (DVD), high-definition digital television (HDTV), video call and video conference all have been introduced into people's daily life. Most of the currently available audio video (AV) systems process voice and image information in a completely digitalized manner to meet the newest technological trend. Different specifications and standards for AV systems have been constantly established, revised and updated, so that the AV systems can provide audio and visual signals with higher quality and can be applied to more different application fields to meet consumers' demands. Digital signals must be transmitted at further increased speed without the need of compression. Currently, there are many standardized digital video interfaces available for use, such as HDMI (high-definition multimedia interface), DVI (digital visual interface) and DisplayPort. Through digitized transmission of signals via these interfaces, images of enhanced quality can be displayed on electronic devices. The above-mentioned interfaces can be electrically connected to an adapter, a set-top box, a DVD player, a personal computer, a video game console, an integrated amplifier, a digital stereo system, etc. to enable long distance transmission of high quality signals at high speed, and are therefore widely welcome among consumers and can be seen everywhere now. The use of these standardized digital video interfaces to transmit video signals at high speed can provide better visual effect.
Most cables for DisplayPort connector, DVI connector and HDMI connector are round cables or flat cables. Inside these cables, there is a plurality of metal conductors, which are respectively surrounded by an insulating layer to prevent short circuit between the metal signal conductors. Each signal pair is further surrounded by a metal shield to prevent crosstalk between the signal pair. While the metal shield can reduce the crosstalk between the signal pair, it makes the whole cable stiff, heavy and inconvenient for use. Further, to connect the cable to the terminals of the connector, it is necessary to strip a length of the metal shield from the signal pair. By doing this, scraps would be produced. Moreover, cables with conductors surrounded by metal shields could not be used with piercing terminals to enable automated assembling of cables.